SATNAV systems used by millions of motorists could become useless next year, it was claimed last night.
Experts warned that the Global Positioning System, which sat navs rely on, could collapse due to a lack of investment in new satellites.

The first replacement satellite had been due to be launched into space in 2007 but will not now be ready until November.

It is unclear whether the satellites currently in orbit will be able to keep the system running until replacements arrive.

The US Congress was told the American air force, which runs the system, had failed to keep the satellites up to date.